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152. Sensitive and high recovery electrochemical sensing of resorcinol by Cd–glutathione complex-modified glassy carbon electrode.

Author

Aslam, Rashida, Fatima, Batool, Hussain, Dilshad, Nawaz, Rahat, Majeed, Saadat, Ashiq, Muhammad Naeem, Qureshi, Tahir Imran, and Najam-Ul-Haq, Muhammad

Subjects
CARBON electrodes, RESORCINOL, ENERGY dispersive X-ray spectroscopy, URIC acid, PHENOLS, ELECTROCHEMICAL sensors
Abstract

Resorcinol belongs to class of phenolic compounds with high medicinal importance due to antiseptic and disinfectant properties. In this research, cadmium–glutathione (Cd–GSH) complex has been synthesised by single sept strategy and used for electrochemical sensing of resorcinol. Synthesised complex is characterised by UV/Visible spectrophotometer, Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS). Cyclic voltammetry (CV), with three-electrode system, is used for sensing of resorcinol. Cd–GSH-modified glassy carbon electrode (GCE) shows redox response for resorcinol and parameters including pH, concentration and scan rate are optimised. Results indicate that peak current of resorcinol is the highest in PBS buffer solution of pH 7.4. Under optimised experimental conditions, the anodic peak current of resorcinol shows linear trend (R2) in the range of 0.996 and limit of detection (LOD) up to 0.3 μM by amperometry, which is significantly higher than some other reported materials. Observed recovery of resorcinol from tap water (113%) and pond water (138%) also justified by Cd–GSH complex-modified electrode. Furthermore, synthesised complex is selective for resorcinol in the presence of higher concentrations of ascorbic acid and uric acid. Good stability and reproducibility up to 30 cycles indicate the potential use of complex as electrochemical sensors. [ABSTRACT FROM AUTHOR]

Published
2021
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156. Scalable Synthesis of Sm2O3/Fe2O3Hierarchical Oxygen Vacancy-Based Gyroid-Inspired Morphology: With Enhanced Electrocatalytic Activity for Oxygen Evolution Performance

Author

Abid, Abdul Ghafoor, Manzoor, Sumaira, Usman, Muhammad, Munawar, Tauseef, Nisa, Mehar Un, Iqbal, Faisal, Ashiq, Muhammad Naeem, Najam-ul-Haq, Muhammad, Shah, Afzal, and Imran, Muhammad

Abstract

Non-platinum-based critically and rationally fabricated electrocatalysts show promising efficiency in electrochemical oxygen evolution reaction (OER) due to their reliability and cost-effectiveness. Herein, a hydrothermally designed oxygen-defective Sm2O3/Fe2O3composite with gyroid morphology provides superior active sites with high porosity and mass charge transport in a catalytic system. All of the fabricated materials were characterized via different analytical techniques. The Sm2O3/Fe2O3hierarchical composite displays an outstanding lower overpotential (272 mV) to attain a current density of 10 mA/cm2and a lower Tafel slope (75 mV/dec) compared to the individual materials Sm2O3and Fe2O3in alkaline media. The remarkable electrocatalytic intrinsic OER performance of oxygen-defective Sm2O3/Fe2O3is ascribed to the strong synergistic effect among both materials due to their unique gyroid structure, and such architecture exhibits extraordinary electrical properties due to its porous structure. Hierarchical Sm2O3/Fe2O3exhibits marvelous activity and stability at an applied potential (0.7 V) with a slight decrease in current density. All of the extraordinary results acquired from electrochemical activity make Sm2O3/Fe2O3a promising electrocatalyst for electrochemical energy generation.

Published
2021
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158. Fabrication of rGO/SrSeO4 nanocomposite as an electrode material with enhanced specific power for supercapacitor applications.

Author

Gohar, Ruqiya Sehrish, Ahmad, Zahoor, Zaki, Zaki Ismail, Imran, Muhammad, Ashiq, Muhammad Naeem, Shafqat, Madeeha, Najam-Ul-Haq, Muhammad, Khan, Waheed Qamar, Shah, Afzal, and Nisar, Jan

Abstract

Fossil fuels are the major source of energy in the world, which are being depleted day by day. Fossil fuels are also polluting the environment by releasing greenhouse gases such as carbon dioxide. To overcome environmental pollution as well as energy crisis, exploration of new ways of storing energy is the need of the time. In the presented work, reduced graphene oxide/Strontium selenate nanocomposite has been synthesized as an electrode material for energy storage devices. The structure of rGO/ SrSeO4 nanocomposite was confirmed by x-ray diffraction while the morphology was investigated by scanning electron microscopy. The electrochemical measurements, such as cyclic voltammetry, galvanostatic charge/discharge, electrochemical impedance spectroscopy and cyclic stability, were also carried out. The synthesized nanocomposite showed excellent specific power of 684.16 W/kg with 3.67 Wh/kg specific energy, which is significantly much better than already reported metal selenide materials. [ABSTRACT FROM AUTHOR]

Published
2021
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159. Enhanced electrochemical properties of silver-coated zirconia nanoparticles for supercapacitor application.

Author

Naeem Ashiq, Muhammad, Aman, Ali, Alshahrani, Thamraa, Faisal Iqbal, Muhammad, Razzaq, Aamir, Najam-Ul-Haq, Muhammad, Shah, Afzal, Nisar, Jan, Tyagi, Deependra, and Fahad Ehsan, Muhammad

Abstract

Silver-coated ZrO2 and individual ZrO2 nanoparticles have been synthesized using the simple reduction and co-precipitation methods, respectively. The synthesized products were examined using the X-ray diffraction, energy-dispersive X-ray and UV–visible spectroscopy, which confirmed the successful synthesis of materials. Scanning electron microscopy and transmission electron microscopy revealed the round-shaped nanoparticles of both materials. The cyclic voltammograms revealed the well-defined redox peaks and recommended the pseudocapacitive nature of the electrodes. The silver-coated zirconia showed higher specific capacitance of 792 F/g at 10 mV/s as compared to individual zirconia (10.22 F/g). Silver-coated ZrO2 also showed good power density of 274.5 W/kg at current density of 5 mA/cm2 through the galvanostatic charge discharge profile. Hence, the results suggest that silver-coated ZrO2 showed improved electrochemical performance as compared individual ZrO2 due to higher electrical conductivity and specific surface area. Hence, silvercoated ZrO2 nanoparticles can be employed as an electrode material for supercapacitor applications. [ABSTRACT FROM AUTHOR]

Published
2021
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173. Fabrication of Piperazine Functionalized Polymeric Monolithic Tip for Rapid Enrichment of Glycopeptides/Glycans

Author

Sajid, Muhammad Salman, Jovcevski, Blagojce, Pukala, Tara Louise, Jabeen, Fahmida, and Najam-ul-Haq, Muhammad

Abstract

Enrichment strategies are designed for the pretreatment of low-abundance glycans and glycopeptides prior to mass spectrometric (MS) analysis. Here, a tip-based strategy is being reported for the enrichment of glycopeptides and glycans using a piperazine modified polymeric monolithic tip. The tip is fabricated using the free radical polymerization. Fast separation (2 min) is achieved under optimized conditions with 20 cycles per step of loading, incubation, washing, and elution followed by MALDI-MS analysis. A total of 25, 22, and 34 glycopeptides covering all glycosylation sites are enriched by the modified tips from tryptic digests of horse radish peroxidase, chicken avidin, and human immunoglobulin G, respectively. Piperazine exhibits high selectivity 1:400 horse radish peroxidase/bovine serum albumin, sensitivity to 100 attomoles, recovery 89.51%, and batch to batch reproducibility (RSD > 1) in glycopeptides enrichment. Piperazine tips also enrich glycans from ovalbumin and human immunoglobulin G. High selectivity (1:1200, ovalbumin/BSA) and detection limit of 100 attomole is attained for glycans and furthermore 58 glycans are enriched from human serum. Thus, piperazine tips can be used as an enrichment tool for swift, cost-effective routine analysis of biological samples for separation of glycopeptides and glycans.

Published
2020
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174. Ultra-fast mass fingerprinting by high-affinity capture of peptides and proteins on derivatized poly(glycidyl methacrylate/divinylbenzene) for the analysis of serum and cell lysates

Author

Günther K. Bonn, Xiaojuan Du, Yang Ke, Honggang Qian, Xiajuan Zou, Douglas T. Gjerde, Christian W. Huck, Najam-ul-Haq Muhammad, Lukas A. Huber, Fang Wei-Gang, Matthias Rainer, Rania Bakry, and Isabel Feuerstein

Subjects
chemistry.chemical_classification, Glycidyl methacrylate, Chromatography, Iminodiacetic acid, Organic Chemistry, Dispersity, Polymer, Mass spectrometry, Divinylbenzene, Analytical Chemistry, chemistry.chemical_compound, Polymerization, chemistry, Sample preparation, Spectroscopy
Abstract

The development of support materials in mass fingerprinting is an important task required for diagnostic markers in conjunction with matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). The material-based approach, which we introduced as material-enhanced laser desorption/ionization (MELDI), focuses not only on different functionalities, but also emphasizes the morphology, i.e. porosity or particle size of the carrier material. As a result, it provides a quick and sensitive platform for effective binding of peptides and proteins out of different biofluids, e.g. serum, spinal fluid, urine or cell lysates, and to subsequently analyze them with MALDI-TOF MS. This approach includes a built-in desalting step for serum protein profiling and is sensitive enough to detect proteins and peptides down to 100 fmol/microL. Here we co-polymerized glycidyl methacrylate (GMA) with divinylbenzene (DVB) using thermal polymerization to yield a GMA/DVB polymer for further modifications. Different affinities have been created, such as immobilized metal ion affinity (IDA-Cu2+), reversed-phase (RP) and anion-exchanger (AX) chromatography. The diverse derivatizations and the dispersity of the particles created by different chemical synthetic approaches were confirmed by characteristic infrared (IR) peaks. The polymerization carried out by non-stirring yielded an average pore radius of 6.1 microm (macro-pores) that enhanced the binding capacity enormously by offering enlarged surface areas. Moreover, atomic absorption spectrometry (AAS) provided the metal content loaded on iminodiacetic acid (IDA) in the case of poly(GMA/DVB)-IDA-Cu2+. To summarize, the optimized MELDI approach is sensitive in its performance, extremely fast and can be adapted to robotic systems for routine analysis, allowing sample preparation in less than 5 min in contrast to the conventional surface-enhanced laser desorption/ionization (SELDI) methods.

Published
2006

175. Eco-friendly route for dyeing of cotton fabric using three organic mordants in reactive dyes.

Author

BAIG, RIAZ, HUSSAIN, DILSHAD, NAJAM-UL-HAQ, MUHAMMAD, RAJPUT, ABDUL WAQAR, and AMJAD, RANA

Subjects
DYES & dyeing, REACTIVE dyes, COTTON textiles, AMMONIUM acetate, MORDANTS
Abstract

Copyright of Industria Textila is the property of Institutul National de Cercetare-Dezvoltare pentru Textile si Pielarie and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Published
2019
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177. Fabrication of a Co-Ni/TiO2Core-Shell Sensor for Label-Free Quantification of Human Serum Albumin in Hepatitis C Virus Patients

Author

Sultan, Noor, Alam, Ayub, Fatima, Batool, Shafi, Sameera, Hussain, Dilshad, Sarwar, Zohaib, Wasim, Muhammad, Majeed, Saadat, Yar, Ahmad, and Najam-ul-Haq, Muhammad

Abstract

Liver cirrhosis is a life-threatening disorder characterized by severe hepatitis C. Early detection of hepatitis C is crucial since HCV infection has few symptoms, and the patient may remain unaware for many years. The early-stage detection can assist in the treatment and prevent further virus transmission. Abnormally varying albumin concentrations in hepatitis C patients can lead to hypoalbuminemia. Herein, a novel Co-Ni/TiO2core–shell-based electrochemical sensor is developed for facile and ultra-sensitive human serum albumin (HSA) detection in HCV patients. Co-Ni/TiO2core shells are fabricated via coprecipitation and hydrothermal methods and used for non-enzymatic detection albumin with high sensitivity, selectivity, and lower detection limits. Cyclic voltammetry, chronoamperometry (CA), and electrochemical impedance spectroscopy (EIS) is performed for albumin detection via Co-Ni/TiO2modified GCE at different scan rates, pH, and concentrations. The linear range and limit of detection (LOD) obtained for the Co-Ni/TiO2electrode are 0–30 μM and 0.019 μM, respectively. The utility of Co-Ni/TiO2electrodes is extended to HSA sensing from HCV-infected patients. Albumin recovery at room temperature ranged from 81.0% to 91.3% in diluted human serum samples. The developed electrochemical analysis method is superior for HSA detection and can be a tool for clinical diagnosis in the future.

Published
2023
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178. Novel multifunctional chitosan-GMA-IDA-Cu(II) nanospheres for high dynamic range characterization of the human plasma proteome

Author

Lijun Zhong, Matthias Rainer, Dan Liu, Isabel Feuerstein, Yuxin Yin, Xiajuan Zou, Jiarou Peng, Bin Yang, Christian W. Huck, Günther K. Bonn, Yaxin Lou, and Najam-ul-Haq Muhammad

Subjects
Proteomics, Biocompatibility, Proteome, Serum albumin, Plasma protein binding, Biochemistry, Analytical Chemistry, Chitosan, chemistry.chemical_compound, Humans, Chromatography, biology, Imino Acids, Reproducibility of Results, Buffer solution, Matrix-assisted laser desorption/ionization, chemistry, Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization, biology.protein, Epoxy Compounds, Methacrylates, Chemical stability, Nanospheres, Protein Binding
Abstract

In this study, we describe characterization of the human plasma proteome based on analysis with multifunctional chitosan-GMA-IDA-Cu(II) nanospheres. Chitosan-GMA-IDA-Cu(II) nanospheres with diameters of 20 to 100 nm have unique properties due to multifunctional chemical moieties, high surface area, high capacity, good dispersibility in buffer solution as well as good biocompatibility and chemical stability which improves their specific interaction with peptides and proteins of the human plasma using different binding buffers. Combining these chitosan-GMA-IDA-Cu(II) nanospheres with MS spectrometry results in a novel strategy which should make it possible to characterize the plasma proteome in a single test. Peptides and proteins adsorbed on the nanosphere can be directly detected by MALDI-TOF-MS. The eluted lower molecular weight peptides and proteins are identified by nano-LC-ESI-MS/MS. A total of 842 unique LMW peptides and 1,682 human unredundant proteins IDs were identified in two different binding buffers, which included relatively low-level proteins (e.g., pg/mL of IL3 Interleukin-3) co-distributed with high-abundance proteins (e.g., 35-55 mg/mL level serum albumin). As such, this nanosphere technique selectively enabled the identification of proteins over a dynamic range of greater than 8 orders of magnitude. Considering this capacity for selective enrichment of peptides and proteins in human plasma, and the large number of LMW peptides and proteins which can be identified, this method promises to accelerate discovery of biomarkers for clinical application.

Published
2010

186. Ultra-fast mass fingerprinting by high-affinity capture of peptides and proteins on derivatized poly(glycidyl methacrylate/divinylbenzene) for the analysis of serum and cell lysates

Author

Matthias, Rainer, Najam-ul-Haq, Muhammad, Christian W, Huck, Isabel, Feuerstein, Rania, Bakry, Lukas A, Huber, Douglas T, Gjerde, Xiajuan, Zou, Honggang, Qian, Xiaojuan, Du, Fang, Wei-Gang, Yang, Ke, and Günther K, Bonn

Subjects
Cell Extracts, Carcinoma, Hepatocellular, Polymethacrylic Acids, Cell Line, Tumor, Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization, Liver Neoplasms, Humans, Polyvinyls, Blood Proteins, Middle Aged, Peptides, Peptide Mapping
Abstract

The development of support materials in mass fingerprinting is an important task required for diagnostic markers in conjunction with matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). The material-based approach, which we introduced as material-enhanced laser desorption/ionization (MELDI), focuses not only on different functionalities, but also emphasizes the morphology, i.e. porosity or particle size of the carrier material. As a result, it provides a quick and sensitive platform for effective binding of peptides and proteins out of different biofluids, e.g. serum, spinal fluid, urine or cell lysates, and to subsequently analyze them with MALDI-TOF MS. This approach includes a built-in desalting step for serum protein profiling and is sensitive enough to detect proteins and peptides down to 100 fmol/microL. Here we co-polymerized glycidyl methacrylate (GMA) with divinylbenzene (DVB) using thermal polymerization to yield a GMA/DVB polymer for further modifications. Different affinities have been created, such as immobilized metal ion affinity (IDA-Cu2+), reversed-phase (RP) and anion-exchanger (AX) chromatography. The diverse derivatizations and the dispersity of the particles created by different chemical synthetic approaches were confirmed by characteristic infrared (IR) peaks. The polymerization carried out by non-stirring yielded an average pore radius of 6.1 microm (macro-pores) that enhanced the binding capacity enormously by offering enlarged surface areas. Moreover, atomic absorption spectrometry (AAS) provided the metal content loaded on iminodiacetic acid (IDA) in the case of poly(GMA/DVB)-IDA-Cu2+. To summarize, the optimized MELDI approach is sensitive in its performance, extremely fast and can be adapted to robotic systems for routine analysis, allowing sample preparation in less than 5 min in contrast to the conventional surface-enhanced laser desorption/ionization (SELDI) methods.

Published
2006

195. Smartphone-Assisted EY@MOF-5-Based Dual-Emission Fluorescent Sensor for Rapid On-Site Detection of Daclatasvir and Nitenpyram

Author

Kanwal, Tehreem, Rasheed, Sufian, Hassan, Mahjabeen, Fatima, Batool, Xiao, Hua-Ming, Musharraf, Syed Ghulam, Najam-ul-Haq, Muhammad, and Hussain, Dilshad

Abstract

Fluorescent metal–organic frameworks (MOFs) are promising sensing materials with tunable and robust structural properties and remarkable luminescent capabilities. In this study, a novel dual-emission fluorescent metal–organic framework (EY@MOF-5) composite is synthesized by a one-pot bottle-around-ship approach. Eosin Y (EY) is encapsulated in MOF-5 to enhance its fluorescence properties and selectivity, effectively addressing typical MOF-5 limitations. EY@MOF-5 serves as a versatile dual-functional fluorescent sensor for two different analytes, daclatasvir (DCT) and nitenpyram (NTP), showing an impressive linear range of 10–200 nM and 0.1–300 μM, with detection limits of 233 pM and 65 nM, respectively. The established method is ultrafast, highly sensitive, and extremely selective for DCT and NTP detection in complex biological and food samples. Fluorescence results are compared and validated with the recommended UPLC method. Then, a smartphone-integrated sensing system is introduced for on-site, real-time, and quantitative analysis of DCT and NTP. The smartphone-assisted intelligent sensing method manifests promising results for DCT and NTP monitoring in biological and food samples, demonstrating its promising potential for the on-site detection of biologically and environmentally significant analytes.

Published
2023
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196. pH-responsive delivery of anticancer galloyl derivatized 5-fluorouracil to MCF-7 cell lines by folic acid functionalized yttrium oxide nanocarrier

Author

Batool, Rafia, Fatima, Batool, Hussain, Dilshad, Imran, Muhammad, Saeed, Ummama, and Najam-ul-Haq, Muhammad

Abstract

The study describes the synthesis of folic acid functionalized yttrium oxide (FA@Y2O3) nanocarrier, modified with galloyl derivatized 5-Flourouracil (GFU) and its anticancer activity. Drug carriers are characterized via FTIR, XRD, SEM, TEM, and Zeta Potential. Considering the tumor-targeting ability of 5-fluorouracil and gallic acid (5FU-GA), a pH-responsive drug delivery system is proposed by combining 5-FU and gallic acid. In a tumor microenvironment (TME), amide bond breaks at low pH and inhibits cancer chemoresistance at a target site, synergistically restricting tumor growth. This pH-responsive drug delivery determines the effectiveness of folic acid functionalized nanocarrier (FA@Y2O3-GFU) in the tumor microenvironment. GFU has substantial therapeutic efficacy, antioxidant activity, anti-inflammatory action, shallow systematic toxicity, and enhanced reactive oxygen species generation in MCF-7 cells. In vitroexperiments are conducted at different pH, time, concentration, and temperature. Results indicate the highest loading efficiency of 81%, faster release rate at 45 °C and pH 6.5.

Published
2023
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197. Antimicrobial Efficacy of Metal-Barbiturate Conjugates Against Pathogenic Strains of Escherichia coli and Staphylococcus aureus

Author

Mahmood Qureshi, Ashfaq, primary, Qadir, Mehmood, additional, Rauf, Abdul, additional, Idrees, Muhammad, additional, Mumtaz, Siara, additional, Najam-ul-Haq, Muhammad, additional, Ismail, Muhammad, additional, Athar, Muhammad, additional, Khushal, Rashid, additional, Riaz, Sara, additional, and Bokhari, Habib, additional

Published
2011
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